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Behavioural ecology and conservation biology of ground pangolins Smutsia temminckii in the Kalahari DesertPietersen, Darren William January 2013 (has links)
Ground pangolins Smutsia temminckii are inconspicuous, mainly nocturnal mammals
that occur at low population densities. As a result, there is scant information available
on the ecology and physiology of this species. To date the handful of studies
focussing on this species were centred in the mesic eastern regions of its range, with
no attention being given to ecological and biological traits in arid environments. To
address these data shortfalls, a study was undertaken in the Kalahari Desert in northwestern
South Africa. Very High Frequency (VHF) transmitters or Global Positioning
System (GPS) loggers were fitted to 16 ground pangolins and their ecology and
physiology studied over a period of three years.
Throughout its range the ground pangolin is increasingly endangered, predominantly
due to anthropogenic threats. Previous studies have identified threats facing this
species, but very few of these studies included quantitative data as to the extent of
these threats. The present study suggests that the main threats to ground pangolins
in southern Africa are electrocution on electrified fences, the traditional medicine
trade, habitat loss, road mortalities and capture in gin traps. Although accidental
poisoning has previously been viewed as a threat, a review of the available literature
suggests that this is not the case and that these views stemmed from two isolated
incidents of captive animals. Electrocutions probably pose the greatest threat to
ground pangolins, with mortality rates of one pangolin per 11 km of electrified fence
per year recorded during this study.
Home range sizes of this arid-zone population are comparable to the home range
sizes recorded in mesic populations. Study animals in the Kalahari had Minimum
Convex Polygon (MCP) home range values of 10.0 ± 8.9 km² SD for adults and 7.1 ±
1.1 km² SD for juveniles, in comparison to the 0.17 – 23.38 km² MCP in Zimbabwe
and 1.3 – 7.9 km2 MCP in mesic north-eastern South Africa. These results are
surprising as arid-zone animals usually have larger home ranges than do their mesic
counterparts. It is hypothesised that this discrepancy is due to the fact that ground
pangolins in the Kalahari are on average 25 – 30 % smaller than their mesic
counterparts. This smaller body size means that individuals require a smaller home
range to meet their dietary requirements, which could be counteracting the trend of
arid-zone individuals requiring larger home ranges.
This research also found ground pangolins to be more active during the day in winter
and nearly entirely nocturnal during summer. These changes in photoperiodicity are
likely driven by adaptations to the extreme climatic conditions present at the study
site rather than predation pressure or changes in food resources, although the latter
may be playing a role as well. By being diurnal in winter, individuals avoid the
extremely cold night-time temperatures, thus saving energy that would otherwise be
spent on maintaining their body temperature. By contrast, becoming nocturnal in
summer allows them to avoid the extreme daytime temperatures, thus conserving
water.
The results of this study reiterate previous findings that ground pangolins are entirely
myrmecophagous and highly selective of the species that they eat. Study animals
were recorded feeding on only four ant and two termite species, representing 7.5 %
and 50 % of the total species richness of each of these families. This is similar to
previous research in mesic savannahs where five ant one termite species constituted
97 % of the ground pangolin’s diet. No seasonal differences in prey selection were
observed, although the species consumed did depend on the habitats that were
available to individual ground pangolins.
This study is the first to investigate the core body temperature (Tb) of a free-ranging
pangolin. These data indicated that Tb fluctuated cyclically between 32 – 35 °C and
reflected the activity periods of the animal, peaking when the animal was active.
When the individual was inactive, Tb steadily decreased, suggesting that it used daily
heterothermy to cope with the low food availability in this unpredictable environment.
In summary, ecological parameters between arid and mesic ground pangolin
populations are similar in some respects, but divergent in others. Arid-zone
populations are smaller overall and show a higher degree of diurnal activity. Despite
this smaller body size, home range values appear to be similar between arid and
mesic populations. Although the prey species eaten by ground pangolins in the
Kalahari differ from prey species in eastern South Africa and Zimbabwe, they
belonged to the same genera and were of similar morphology and ecology. The core
body temperature results confirm findings from previous captive studies that pangolin
body temperatures are lower than those of other eutherian mammals of a similar size. Furthermore, these data indicate that core body temperature is a lot more
variable than previously believed, and thus warrants further study. Overall ground
pangolin densities in the Kalahari appear to be double those in eastern South Africa
and Zimbabwe, although it is unclear whether this is genuine or whether it is an
artefact of individuals being easier to locate in the Kalahari. This study also confirmed
that electrocutions are probably the greatest threat to this species, and new threats
such as accidental capture in gin traps and road mortalities have also come to light. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Zoology and Entomology / unrestricted
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Efficient global gravity field determination from satellite-to-satellite trackingHan, Shin-Chan 07 November 2003 (has links)
No description available.
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USING COOPERATIVE RESEARCH AND DEVELOPMENT AGREEMENTS (CRADA) TO REDUCE THE TRANSITION TO PRODUCTION RISK OF A MISSILE TELEMETRY SECTIONKujiraoka, Scott R., Fielder, Russell G. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Joint Advanced Missile Instrumentation (JAMI) Program’s main thrust has
been the integration of Global Positioning System (GPS) tracking technology into the
Department of Defense (DoD) Missile Test Ranges. This technology could be used for
Time, Space, Position, and Information (TSPI), Flight Termination (FTS), or End Game
Scoring purposes. However the Program’s main goal is to develop Proof-of-Concept
components only. Transitioning Missile technology developed by the Government to
Private Industry, so that it can be economically mass produced, has been quite a
challenge. Traditionally, private industry has had to bid on proposals without much
detailed information on how these components have been designed and fabricated.
These unknown risks, Non-Recurring Engineering (NRE) and Missile Flight Qualification
costs, routinely have significantly increased the price of these procurement contracts.
In order so that the Fleet can economically utilize these components in the field,
Cooperative Research and Development Agreements (CRADA) between the
Government and Private Industry have been used to successfully transition Government
developed technology to mass production. They can eliminate the NRE and flight
qualification costs to provide for an economical and low risk method of providing the
Fleet with the latest advances in GPS Tracking Technology. This paper will discuss
how this is currently being accomplished in the development of a conformal wraparound
instrumentation antenna for a five-inch diameter Missile Telemetry (TM) Section.
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DIFFERENTIAL GPS ENHANCES TEST CAPABILITIES OF DOMESTIC AND INTERNATIONAL PROGRAMSWallace, Keith, McCleaf, Tim, Pham, Tri 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / A system was developed using capabilities from the Range Applications Joint Program
Office (RAJPO) GPS tracking system and the ACMI Interface System (ACINTS) to
provide tracking data and visual cues to experimenters. The Mobile Advanced Range Data
System (ARDS) Control System (MACS) outputs are used to provide research data in
support of advanced project studies. Enhanced from a previous system, the MACS
expands system capabilities to allow researchers to locate where Digital Terrain Elevation
Data (DTED) is available for incorporation into a reference data base.
The System Integration Group at Veda Incorporated has been supporting Wright
Laboratories in the ground-based tracking and targeting arena since 1989 with the design,
development, and integration of four generations of real-time, telemetry-based tracking
aids. Commencing in Q3 1995, Veda began developing a mobile, transportable system
based on the RAJPO GPS tracking system. The resulting system architecture takes
advantage of the front end processor (FEP) used in the three previous generations of
interface systems built for Wright Laboratories, thus maximizing hardware and software
reuse. The FEP provides a computational interface between the GPS tracking system and
the display (operator) system.
The end product is a powerful, flexible, fully mobile testbed supporting RDT&E
requirements for Wright Laboratories, as well as to other U.S. and foreign research
organizations. The system is rapidly reconfigurable to accommodate ground-based
tracking systems as well as GPS-based systems, and its capabilities can be extended to
include support for mission planning tools, insertion of virtual participants such as DIS
entities, and detailed post-mission analysis.
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Checking the integrity of Global Positioning Recommended Minimum (GPRMC) sentences using Artificial Neural Network (ANN)Hussain, Tayyab January 2009 (has links)
<p>In this study, Artificial Neural Network (ANN) is used to check the integrity of the Global Positioning Recommended Minimum (GPRMC) sentences. The GPRMC sentences are the most common sentences transmitted by the Global Positioning System (GPS) devices. This sentence contains nearly every thing a GPS application needs. The data integrity is compared on the basis of the classification accuracy and the minimum error obtained using the ANN. The ANN requires data to be presented in a certain format supported by the learning process of the network. Therefore a certain amount of data processing is needed before training patterns are presented to the network. The data pre processing is done by the design and development of different algorithms in C# using Visual Studio.Net 2003. This study uses the BackPropagation (BP) feed forward multilayer ANN algorithm with the learning rate and the momentum as its parameters. The results are analyzed based on different ANN architectures, classification accuracy, Sum of Square Error (SSE), variables sensitivity analysis and training graph. The best obtained ANN architecture shows a good performance with the selection classification of 96.79 % and the selection sum of square error 0.2022. This study uses the ANN tool Trajan 6.0 Demonstrator.</p>
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Les mesures synchronisées par GPS pour l'amortissement des oscillations de puissance dans les grands réseaux électriques interconnectésSnyder, Aaron Francis 18 October 1999 (has links) (PDF)
Les grands réseaux électriques sont utilisés de plus en plus près de leur limite de stabilité Ceci est dû aux contraintes économiques, politiques et écologiques obligent tes opérateurs1 à exploiter leurs réseaux à la limite de sécurité. Cependant faire fonctionner un réseau trop près de ses limites crée des oscillations de puissance entre les différentes centrales et parties des réseaux liées par des interconnexions assez faibles (en, terme de nombre de lignes d'interconnexion). Ces oscillations " inter-régions " se manifestent sur les arbres des machines concernées (oscillations électro-mécaniques) et affectent la stabilité du réseau. Un moyen efficace pour remédier à ce problème consiste en une utilisation d'un correcteur dit RFC (Remote Feedback Controller). Ce correcteur utilise comme signaux d'entrée des grandeurs provenant de machines distantes du point d'installation du correcteur Ces signaux sont synchronisés par des satellites GPS (Global Positioning System). Les outils d'analyse et de calcul comme l'optimisation convexe avec contraintes LMI (inégalités matricielles linéaires), peuvent permettre le réglage de ce correcteur. Dans te cadre de cette thèse, le travail réalisé traite du problème de la conception et de l'emplacement d'un correcteur RFC utilisant des signaux d'entrée locaux et lointains synchronisés. par les satellites GPS. Les. techniques de programmation convexe avec des contraintes LMÏ sont utilisées pour le réglage de ce correcteur pour l'amortissement des oscillations inter-régions dans lés réseaux électriques. Les correcteurs réalisés sont ensuite implantés dans deux réseaux tests à 4 à 29 machines. Grâce aux techniques LMI les correcteurs sont robustes dans une grande plage de points de fonctionnement des réseaux tests et sont plus performants que les correcteurs traditionnels. De plus, ces correcteurs ne sont pas perturbés par d'éventuels problèmes dus à l'éloignement des signaux, notamment par un retard du signal ou par sa perte éventuelle.
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Checking the integrity of Global Positioning Recommended Minimum (GPRMC) sentences using Artificial Neural Network (ANN)Hussain, Tayyab January 2009 (has links)
In this study, Artificial Neural Network (ANN) is used to check the integrity of the Global Positioning Recommended Minimum (GPRMC) sentences. The GPRMC sentences are the most common sentences transmitted by the Global Positioning System (GPS) devices. This sentence contains nearly every thing a GPS application needs. The data integrity is compared on the basis of the classification accuracy and the minimum error obtained using the ANN. The ANN requires data to be presented in a certain format supported by the learning process of the network. Therefore a certain amount of data processing is needed before training patterns are presented to the network. The data pre processing is done by the design and development of different algorithms in C# using Visual Studio.Net 2003. This study uses the BackPropagation (BP) feed forward multilayer ANN algorithm with the learning rate and the momentum as its parameters. The results are analyzed based on different ANN architectures, classification accuracy, Sum of Square Error (SSE), variables sensitivity analysis and training graph. The best obtained ANN architecture shows a good performance with the selection classification of 96.79 % and the selection sum of square error 0.2022. This study uses the ANN tool Trajan 6.0 Demonstrator.
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Advanced Nonlinear Techniques for Low Cost Land Vehicle NavigationGeorgy, Jacques 27 July 2010 (has links)
Present land vehicle positioning and navigation relies mostly on the Global Positioning System (GPS). However, in urban canyons, tunnels, and other GPS-denied environments, the GPS positioning solution may be interrupted or suffer from deterioration in accuracy due to satellite signal blockage, poor satellite geometry or multipath effects. In order to achieve continuous positioning services, GPS is augmented with complementary systems capable of providing additional sources of positioning information, like inertial navigation systems (INS). Kalman filtering (KF) is traditionally used to provide integration of both INS and GPS utilizing linearized dynamic system and measurement models. Targeting low cost solution for land vehicles, Micro-Electro-Mechanical Systems (MEMS) based inertial sensors are used. Due to the inherent errors of MEMS inertial sensors and their stochastic nature, which is difficult to model, KF has limited capabilities in providing accurate positioning in challenging GPS environments.
This research aims at developing reliable integrated navigation system capable of demonstrating accurate positioning during long periods of challenging GPS environments.
Towards achieving this goal, Mixture Particle filtering (MPF) is suggested in this research as a nonlinear filtering technique for INS/GPS integration to accommodate arbitrary inertial sensor characteristics, motion dynamics and noise distributions. Since PF can accommodate nonlinear models, this research develops total-state nonlinear system and measurement models without any linearization, thus enabling reliable integrated navigation and mitigating one of the major drawbacks of KF. Exploiting the capabilities of PF, Parallel Cascade Identification (PCI), which is a nonlinear system identification technique, is used to obtain efficient stochastic models for inertial sensors instead of the currently utilized linear models, which are not adequate for MEMS-based sensors. Moreover, this research proposes a method to update the stochastic bias drift of inertial sensors from GPS data when the GPS signal is adequately received. Furthermore, a technique for automatic detection of GPS degraded performance is developed and led to improving the performance in urban canyons.
The performance is examined using several road test experiments conducted in downtown cores to verify the adequacy and the benefits of the methods suggested. The results obtained demonstrate the superior performance of the proposed methods over conventional techniques. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2010-07-23 20:27:02.12
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Avaliação do posicionamento plano-altimétrico com receptor gps em diferentes tipos de uso do solo /Itame, Otávio Yassuo, 1956- January 2008 (has links)
Orientador: Zacarias Xavier de Barros / Banca: José Milton Arana / Banca: Osmar Delmanto Junior / Banca: Lincoln Gering Cardoso / Banca: Vilmar Antonio Rodrigues / Resumo: Neste trabalho, foram realizados levantamentos topográficos para a avaliação do efeito da cobertura vegetal, na recepção de sinais GPS, para obtenção de posicionamento tri-dimensional, considerando os estudos realizados em diferentes tipos de uso do solo. Vértices foram implantados em diferentes tipos de uso do solo; em área com pastagem, com plantação de seringueiras e com eucaliptos, e as suas posições determinadas com estação total, nivelamento geométrico e com receptores GPS. Na avaliação do posicionamento altimétrico adotou-se como valores de referência os desníveis determinados com o nivelamento geométrico para avaliação dos dados obtidos com receptores GPS. As coordenadas planimétricas obtidas com receptores GPS foram analisadas utilizando-se com valores de referência os dados obtidos com a estação total. No levantamento topográfico com estação total foram adotadas as prescrições estabelecidas nas Normas da Associação Brasileira de Normas Técnicas (ABNT) NBR 13.133, Execução de Levantamentos Topográficos, para poligonais do tipo IVP. Foi realizada a análise de exatidão e de precisão do posicionamento tridimensional, adotando como padrão a NBR 13133 da ABNT para a classe do levantamento executado. Para aplicações do GPS na altimetria há necessidade do conhecimento da ondulação geoidal (N), que neste trabalho, para a sua determinação foram coletados dados com receptor na referência de nível (RN). Os resultados obtidos indicam que cuidados especiais devem ser tomados nos levantamentos com receptores GPS em áreas com cobetura vegetal, pois estas interferem na propagação das ondas eletromagnéticas provenientes dos satélites podendo inviabilizar o posicionamento. / In this work, topographic surveys were carried out in order to evaluate the effect of vegetal cover, on the reception of GPS signals, for 3D positioning, considering studies to be made in different types of land use. Points were set up on different types of land use, in areas containing grass, rubber trees and eucalyptus, which had their positions defined using a total station, geometric leveling and GPS receivers In the evaluation of height positioning it was adopted as reference values the height differences determined by geometric levelling in order to evaluate data obtained through GPS receivers. Planimetric coordinates obtained by using GPS receivers were analysed using as reference values the data obtained using a total station. During the topographic survey using a total station the recommendations set up by the Brazilian Association for Technical Rules (ABNT) NBR 13.133, regarding the execution of topographic surveys, for transverses of type IVP. Accuracy and precision analysis was made on the 3D positioning, also considering ABNT NBR 13.133, for the class of topographic survey which was carried out. In order to apply GPS on height positiong it is necessary to know the geoidal ondulation (N) and, in this work, N was computed based upon data acquired employing receivers at the level reference (RN). The results obtained indicate that special care must be taken during the surveys carried out with the use of GPS receivers on areas with vegetal cover, because it causes interference in the propagation of electromagnetic waves from the satellite which can even make the positioning become unviable. / Doutor
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Utilização do sistema de posicionamento global para monitoramento de transporte fretado / Monitoring charter bus service using global positioning systemSilva, Camila Maria de Paiva e 22 December 2006 (has links)
Orientador: Maria Teresa Françoso / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T02:35:13Z (GMT). No. of bitstreams: 1
Silva_CamilaMariadePaivae_M.pdf: 5263797 bytes, checksum: 09760343e8c6a05923be7cf27642b699 (MD5)
Previous issue date: 2006 / Resumo: Este trabalho visa destacar as vantagens e os pontos que devem ser tratados em um sistema AVL (Automatic Vehicle Location), baseado nas tecnologias de posicionamento por satélites e transmissão de dados via rede de telefonia móvel, quando aplicado ao transporte coletivo por fretamento. Neste sentido, três linhas de ônibus fretado que atendem funcionários da Universidade Estadual de Campinas foram monitorados por um período de 07 semanas no trajeto bairro-universidade. O módulo de rastreamento possibilitou a coleta eletrônica de dados de operação do veículo. Também foram registrados, manual e eletronicamente, informações sobre os usuários do serviço. Os dados coletados foram transmitidos via GPRS (General Packet Radio Service) para a central de controle e disponibilizados na rede mundial de computadores em tempo real. Foram verificados os pontos de parada e os itinerários e foi feita uma análise financeira das linhas de fretamento da Unicamp monitoradas durante a pesquisa. O monitoramento de transporte coletivo fretado, relatado neste trabalho de maneira provavelmente inédita, possibilitou a obtenção de dados para gerência e controle do serviço de fretamento. Observou-se, como esperado, que o sistema permite de maneira eficiente o acompanhamento da operação com registro de posições e velocidades desenvolvidas pelo veículo monitorado e dos locais de parada e itinerários cumpridos. No caso em questão, entre as vantagens obtidas destaca-se a possibilidade de realizar uma fiscalização mais efetiva, tanto pela operadora do transporte, como pela universidade, controlando os horários programados, os itinerários e os passageiros. São apresentadas sugestões para melhoria do sistema de rastreamento utilizado / Abstract: This research aims to point out the advantages and what still needs to be improved in an Automatic Vehicle Location ¿ AVL - system applied to the charter bus service. The sample of three charter bus lines serving Campinas University (Unicamp)¿s workers on their way from home to office, in a seven weak period. The AVL equipment was used to collect electronic operational data. Users information were collected automatically and manually. These data were sent through GPRS (General Packet Radio Service) to the control station and become available in the internet in real time. The itinerary and the bus stops were verified, and a financial analysis of these three lines were made. This could conclude that the system allows monitoring vehicle position and speed, bus stops, traffic points, etc. - supplying data for management and control of the service. It has showed that AVL, when applied in the Unicamp¿s fleet, support better management and control of routes and timetables. In this work it is also proposed improvements in the equipment that has been used. / Mestrado / Transportes / Mestre em Engenharia Civil
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